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Results tagged with perfect-numbers
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user 65801
A perfect number is a positive integer that is equal to the sum of its proper positive divisors.
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On odd perfect numbers $N$ given in the Eulerian form $N = {q^k}{n^2}$, Part II
In general there is a factorization $\sigma(q^{k-1}) = 1+q+\ldots+q^{k-1} = \frac{q^k-1}{q-1} = \prod_{d\mid k, d>1} \Phi_d(q)$. Here $\Phi_d$ is the $d$'th cyclotomic polynomial, defined as the minim …
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